Plumbing fitting



FIG. 1 is a top perspective view of my new design for the plumbing fitting;

FIG. 2 is a bottom perspective view of my new design for the plumbing fitting;

FIG. 3 is a side view of my new design for the plumbing fitting;

FIG. 4 is a top plan view of my new design for the plumbing fitting; and,

FIG. 5 is a bottom view of my new design for the plumbing fitting. 

CLAIM The ornamental design for a plumbing fitting, as shown and described. 